Estimating indigenous cultural values of freshwater: A choice experiment approach to Māori values in New Zealand

Ecological Economics 118 (2015) 207–214

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Surveys

Estimating indigenous cultural values of freshwater: A choice experiment approach to Māori values in New Zealand Sini Miller ⁎, Peter Tait, Caroline Saunders Agribusiness and Economics Research Unit, Lincoln University, New Zealand

a r t i c l e

i n f o

Article history: Received 17 December 2014 Received in revised form 12 May 2015 Accepted 25 July 2015 Available online xxxx

a b s t r a c t Indigenous cultural values of freshwater resources are important in many communities, however, they are not always included in non-market valuations. While measuring cultural values can be challenging, the omission could lead to incomplete information for policy implications. This paper reports results of a choice experiment study which included a Māori cultural attribute. This attribute was considered alongside economic, recreational and environmental attributes of freshwater, all of which are impacted by the changing land-use in Canterbury, New Zealand. The results show positive willingness-to-pay for all attributes where change from poor to excellent habitat quality ($123/year) was valued highest. The cultural attribute, specifically, was valued in mid-range between economic, recreational and environmental attributes. Estimated willingness-to-pay were $40/year by Māori, and $28/year by the general public, to enhance Māori cultural attributes, where Māori willingness-topay is indicative only due to a small number of respondents. Importantly, this demonstrates support for the management outcome for cultural attributes, which is valued not only by those who directly participate in this use. This suggests that non-market valuation practitioners should be aware of indigenous cultural values, the omission of which could have impacts on welfare estimates and subsequent decision making. © 2015 Elsevier B.V. All rights reserved.

1. Introduction Freshwater resources around the world are associated with many direct and passive-use values such as irrigation, recreation and environmental quality that are important for society. In many places, these resources are also culturally important. In New Zealand, for example, freshwater is considered as taonga (treasure) by the indigenous Māori culture providing fundamental cultural values and being important in maintaining cultural traditions and knowledge in contemporary society to be passed on to future generations (Harmsworth et al., 2011; Ruru, 2009; Te Rūnanga o Ngāi Tahu, n.d.). While cultural values are often classified as passive use values (Venn and Quiggin, 2007) due to their intangible or spiritual aspects, waterways also provide resources for cultural products important to Māori such as mahinga kai — an inclusive term for traditional food and resource gathering (Tipa and Teirney, 2003). The concept of including cultural values as benefits provided by ecosystem services is not novel (MEA, 2005; UK NEA, 2011). However, there exists a need for an improved incorporation of different social and cultural benefits in empirical research and practice (Chan et al., 2012; Gould et al., 2014; Klain et al., 2014). This goal is challenging as ⁎ Corresponding author at: Agribusiness and Economics Research Unit, PO Box 85084, Lincoln University, Lincoln 7647, Canterbury, New Zealand. E-mail addresses: [email protected] (S. Miller), [email protected] (P. Tait), [email protected] (C. Saunders).

http://dx.doi.org/10.1016/j.ecolecon.2015.07.031 0921-8009/© 2015 Elsevier B.V. All rights reserved.

culture itself is a complex construct that embodies many issues including definition, classification and measurement (Satterfield et al., 2013). Satterfield et al. (2013) consider three different measurement approaches for traditional cultural outcomes in environmental management: natural metrics, proxy measures and constructed scales when no other suitable measures exist. Regardless of which metric is used, if these cultural values are impacting on resource allocation decisions in some way, they should not be ignored in economic analysis (Throsby, 2001) or practical management (Klain et al., 2014). In New Zealand, regional water management, under the Resource Management Act (1991), has adopted an integrated approach that recognises the needs of diverse elements of freshwater use that contribute to wellbeing in society (e.g. Canterbury Mayoral Forum, 2009). Economic valuation tools can provide information for cost-benefit analysis of policy alternatives to compare possible directions in resource management. However, assessment of the benefits from different uses of water is often difficult due to a lack of commensurable data; environmental and indigenous cultural values in particular may have little or no association with market data. This common omission can potentially lead to incomplete policy implications being formed. Economic and cultural values, although not perfectly comparable due to their different origins and theories of value (Throsby, 2001), are anthropocentric and based on people's preferences. The economic approach of measuring values based on trade-offs may be challenging within the context of intangible cultural values and often have no substitutes (Awatere, 2005; Throsby, 2003; Venn and Quiggin, 2007). However, resource

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management and allocation decisions require information concerning how cultural values are viewed in relation to competing values of water. Therefore, choice experiments (CEs) provide one practical way to assess and compare the values of benefits when the goods and services have no markets, covering both use and passive-use values within the total economic value framework (Bateman et al., 2002; Oleson et al., 2015). This method facilitates the identification of willingness-to-pay (WTP) for and trade-offs across various attributes in the environmental resource valuations (Hoyos, 2010). CE has an established literature in environmental valuations (Hoyos, 2010); and while this literature includes a scant body of positive evidence regarding the role of cultural values in freshwater management (Birol et al., 2006; Carlsson et al., 2010; Rolfe and Windle, 2003; Zander et al., 2013; Zander and Straton, 2010), no New Zealand studies have focused on constructing of an indigenous cultural specific attribute allowing for explicit estimation of preferences. One reason for the lack of this valuation is the contention of placing a dollar value on culture and nature (Awatere, 2005; Chan et al., 2012; Steenstra, 2009; Venn and Quiggin, 2007). While these concerns should be recognised, omitting relevant factors from the valuation may, however, lead to biased mean and welfare estimates as well as larger choice variation in CEs (Hoyos, 2010; Islam et al., 2007; Johnston et al., 2013). Subsequent possible problems include undermining cultural benefits and not communicating what matters to the public (Chan et al., 2012). Including these values, on the other hand, facilitates planning of initiatives such as spatial planning, development schemes or payments for ecosystem services (Chan et al., 2012). This study reports the results from a CE survey of residents in Canterbury, New Zealand. The central objective in this study was to identify how the traditional Māori cultural attribute of freshwater is valued by the general public, including Māori and non-Māori, by explicitly separating this from other environmental, economic and social freshwater attributes. The secondary objective was to identify differences in preferences between Māori and non-Māori towards this cultural attribute. In other words, how much Māori are willing to pay for their traditional use practices, and non-Māori WTP for Māori use of freshwater resources. Internationally, this extends the literature assessing public preferences towards the management of indigenous cultural values in freshwater assets; while it also provides information for those involved in natural resource policy decisions, particularly in New Zealand. This study also contributes to the literature that aims to bridge both cultural and environmental valuation research to recognise freshwater resources as potential sources of cultural value, which can be challenging to measure. A substantial body of CE applications exist estimating WTP for freshwater attributes in varying contexts (Kragt, 2013; Marsh, 2012; Rolfe and Brouwer, 2012; Scarpa et al., 2005; Tait et al., 2012). Similarly, a significant amount of non-market valuation applications exist specific to the cultural heritage literature predominantly within a built environment context including museums and monuments (Choi et al., 2010; Domínguez-Torreiro and Soliño, 2011; Lourenço-Gomes et al., 2014; Mazzanti, 2003; Tuan and Navrud, 2007). However, literature spanning these applied contexts that combines indigenous cultural and environmental elements of freshwater is limited. In Australia, two CE studies exploring the trade-offs in river management included protection of cultural sites (Rolfe and Windle, 2003) and waterholes (Zander et al., 2013; Zander and Straton, 2010) important to Aboriginal people. In Sweden, as part of a larger environmental management CE study, Carlsson et al. (2010) considered ancient remains broadly as cultural assets in lakes and streams while Birol et al. (2006), in Greece, included a cultural element as part of research and education attribute in the protection and restoration of a wetland. In addition, Perni et al. (2012) and Turner and Willmarth (2014) used contingent ranking method to explore the importance of cultural heritage in ecological river restoration work in Spain and as a component of natural park management in the United States, respectively. Overall, these studies have shown that cultural values provide important benefits for communities (Birol

et al., 2006; Carlsson et al., 2010; Perni et al., 2012; Rolfe and Windle, 2003; Turner and Willmarth, 2014) with one study finding improvement in indigenous cultural ecosystem services with highest WTP of the different river attributes (Zander et al., 2013). Preferences towards cultural outcomes can also be linked to different cultural populations; in Australia, cultural uses have been found important for both, the indigenous population and non-indigenous Australians, although lesser extent for the latter (Rolfe and Windle, 2003; Zander and Straton, 2010). Preferences towards cultural uses may also depend on respondents' socio-economic characteristics such as income and education; their attitudes such as environmental consciousness and bequest motives (Birol et al., 2006; Zander et al., 2013); or that the respondents live in close proximity to a specific waterway (Zander et al., 2013). Cultural attributes have also been found to be prone to attribute nonattendance in CE (Carlsson et al., 2010; Zander and Straton, 2010) which contradicts the theoretical expectation that the respondents make complete trade-offs which, in turn, can bias the WTP estimates (Kragt, 2013). While the issue of attribute non-attendance is a standard concern in CE, it can provide additional insights about the general public's attitudes towards the cultural values in freshwater context. In New Zealand, a number of CE studies have considered diverse environmental, economic and social attributes of freshwater resources (Kerr and Sharp, 2008; Marsh, 2012; Marsh and Phillips, 2012; Tait et al., 2012). While some of these studies included attributes that could be considered to overlap with Māori concepts (Andersen et al., 2012; Kerr and Swaffield, 2007, 2012; Marsh et al., 2011), they have not explicitly considered the value for a traditional Māori cultural attribute. Notably, Andersen et al. (2012) explored differences in preferences for environmental and societal attributes of Waikato River between Māori and non-Māori, with overall findings suggesting similarities rather than differences. In the context of road development, Awatere (2005) found that Māori were more likely to favour improved biodiversity benefits in roadside environments compared to non-Māori. Regarding marine life conservation, Chunn et al. (2013) found that maintaining cultural practices was considered important to the public. The paper proceeds next describing method and survey development in Section 2. Section 3 reports the CE results discussed in relation with relevant literature. The last section concludes the paper providing policy implications and suggests future directions in cultural valuation research. 2. Material and Methods Choice experiment method was selected to estimate the general public's WTP for, and trade-offs between economic, environmental, social and cultural aspects of wellbeing associated with freshwater management in Canterbury, New Zealand. The popularity of this method pertains to its flexibility across different research contexts where the same principles apply: the survey respondents are required to make choices across given alternatives described by multiple attributes where the theoretical assumption is that people select the alternatives that provide them with highest utility (Louviere et al., 2000; Train, 2003). 2.1. Study Context: Canterbury Rivers Canterbury is the largest region in the South Island of New Zealand. In this region, freshwater resources have been under significant pressure driven by land-use changes and agricultural intensification, associated mainly with conversion to dairy. Dairying is a more intense land-use type in this naturally dry area and requires irrigation (Saunders and Saunders, 2012) while discharging relatively higher amounts of contaminants, such as nutrients, into waterways compared to dryland sheep farming (PCE, 2013). There is also uncertainty regarding the impacts of ongoing irrigation development in the region on freshwater quality (Robson, 2014); for Māori, changes in water quality

S. Miller et al. / Ecological Economics 118 (2015) 207–214

are a fundamental concern with impacts on habitat quality and cultural values on waterways (Tipa, 2014). While current planning and practical management frameworks consider care for water quality, particularly through the nutrient limit-setting guidelines, they also are obliged to a broader range of outcomes (Canterbury Mayoral Forum, 2009; Duncan, 2014; Robson, 2014) that impact societal wellbeing, such as indigenous cultural values. 2.2. Survey Development The attribute selection process involved a comprehensive literature review of what attributes have been included in past relevant CEs as well as what water quality indicators exist in New Zealand, especially in Canterbury. A focus group discussion reflected a diverse range of community values and was used primarily to guide selection of attributes that were most important, and to explore how to describe attributes in the survey. Final attribute selection combined focus group findings with policy relevant variables. Importantly, the range of attribute levels was based on possible outcomes under land-use changes. For biophysical attributes this was established by surveying appropriate regional freshwater scientists about possible levels of outcomes subject to intensified land-use and irrigation development. This process assured policy relevancy, measurability and public saliency of the final attributes (Blamey et al., 2002). The final non-cost attributes included two verbal scales (environmental and cultural attributes) and two numeric ones (jobs and swimming sites) based on the existing indicators as described below. The first attribute (Table 1) is the number of jobs associated with agricultural land-use and conveys the contribution that water use for irrigation makes to the regional economy. The attribute levels were generated using a 30,000 hectare irrigation development scenario in Canterbury (Robson, 2014) where projections from the Canterbury Irrigation Model (Saunders and Saunders, 2012) resulted an estimate of 173 new jobs (or 0.0058 jobs per 1 ha of irrigated land). Next, rivers provide habitat for flora and fauna which forms the second attribute. While a wide variety of metrics have been used in CEs to indicate changes in environmental freshwater quality (Kerr and Swaffield, 2007), this study used a single assessment based on the Quantitative Macroinvertebrate Community Index (QMCI), which is frequently used in the management decisions as a proxy for a common indicator of ecological quality. The QMCI is developed specific to New Zealand rivers and it describes changes in water quality derived from invertebrate sensitivity to pollution and changes in the surrounding environment (Stark and Maxted, 2007). Possible social impacts related to irrigation development include recreational values. Thus the third attribute focused on swimming water quality (SWQ) where attribute levels were measured as the proportion of popular sites in the region being suitable for swimming. This is based on the Suitability for Recreation Grade assessment updated each summer (Environment Canterbury, 2012). The levels range from none being suitable (0%) to the policy target of 80% (Canterbury Water, n.d.).

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The fourth attribute reflects indigenous Māori cultural values and a number of potential cultural measures were considered. These measures commonly include more than one element and are based on knowledge of cultural values associated with freshwater in order to collect information important for Māori which can be useful for environmental management (Harmsworth et al., 2011; Pauling and Arnold, 2008; Tipa and Nelson, 2008; Tipa and Teirney, 2003). The main difference between indigenous cultural and western-scientific indicators is that cultural indicators are typically more subjective, qualitative and holistic, requiring in-depth Māori knowledge (Harmsworth et al., 2011). This study used a constructed scale measure (Satterfield et al., 2013) based on cultural knowledge. This included forming a variable indicating the level of water quality related to mahinga kai (MK) derived from the Cultural Health Index (CHI) primarily developed using Māori communities' in-depth knowledge (Tipa and Teirney, 2003). CHI includes three separate components (traditional association, MK and cultural stream health) where MK is composite of many facets including species availability, ongoing abilities to harvest and access the sites, and perceptions of site use. This was chosen to reflect Māori values that have maintained importance in contemporary society (Tipa and Teirney, 2003) and that been included as a water quality monitoring tool in policy targets (Canterbury Water, n.d.). The levels range from exceptional, where an abundant and good range of mahinga kai species are present on a site that is significant for customary food gathering purposes, to poor where mahinga kai species are absent. Finally, protection and improvements in the above freshwater outcomes do not come without cost. Here this was covered in the payment attribute (COST) of changes in household annual rates for a period of five years. While Canterbury residents already pay an amount in their rates for water management, focus group participants agreed with the idea of increases in rates if better quality waterways resulted. The variation in the level range was guided by recent studies (Marsh and Phillips, 2012; Tait et al., 2012). The final survey included fifteen choice sets for all respondents where they faced choices across three alternatives (Fig. 1). Two of the alternatives (A and B) included management changes and were generated by N-Gene™ software. The selected choice sets had the smallest Derror from a fractional factorial D-efficient experimental design using point estimate priors based on previous Canterbury studies (Kerr and Swaffield, 2007; Marsh and Phillips, 2012; Tait et al., 2012). All priors except COST were assumed to be positive. The design also included two-way interactions (QMCI*MK, SWQ*MK, QMCI*SWQ) in order to explore attribute causal-relationships (Blamey et al., 2002). The third alternative was a constant base alternative representing an approximation of the status quo (SQ) situation (Canterbury Mayoral Forum, 2009; Environment Canterbury, 2012; Golder Associates, 2011) in which water management does not change; with this there is no additional cost but no improvements either. The survey was framed to consider all rivers in the region and it consisted of four parts. The first part included questions of general knowledge, experience and attitudes towards different use and nonuse values related to waterways in the region. Next, the CE was

Table 1 Attributes and attribute levels. Element of wellbeing

Attribute

Employment Environment Social/recreation Cultural

Number of JOBS QMCI: water quality and habitat SWQ: % of suitable swimming sites MK: customary Māori food gathering

Payment

COST to Canterbury households ($NZ/year) for a period of 5 years

Levels Alternatives A and B

Status quo alternative

−173, 0, +173, +346 Poor, fair, good, excellent 0%, 20%, 40%, 60%, 80% Poor, below average, average, above average, exceptional +25, +50, +75, +100, +125

0 Fair 20% Below average 0

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Fig. 1. Example of a choice set.

introduced with respondents asked to consider trade-offs across freshwater attributes within a context of water management outcomes. This included a description of the attributes and an example choice set. The remaining two parts of the survey included validating questions regarding choice difficulty, reasons for SQ-behaviour and attribute attendance; and respondent demographics. In November 2012, a random stratified sample of 1500 Canterbury residents on the general Electoral Roll were mailed the survey instrument. Another 500 surveys were sent to people from a specific Māori Electoral Roll in order to facilitate testing cultural identity-based differences in preferences. A reminder postcard was sent to non-respondents in the third week following initial posting.

community and moreover that some people from the random sample will have been moved from the listed address. The key socio-demographic characteristics of respondents are summarised in Table 2 where the sample had a higher proportion of people with higher education levels compared to the general population of Canterbury. Regarding respondents' ethnicity, 11% were Māori. While slightly higher than the Canterbury average, this was insufficient for split-sample analysis between Māori and non-Māori populations. In addition, looking at the first two columns, it appears that overall both samples (non-Māori and Māori) have similar characteristics.

3. Results and Discussion

The data-analysis of respondent choices focuses on estimating the likelihood of different alternatives been selected based on the functions of underlying attribute combinations (Louviere et al., 2000; Train, 2003). For this analysis, a range of alternative statistical models can be considered which vary depending on the assumptions about heterogeneity of preferences, correlation patterns and representation of the error, or unobserved, component associated with choices. The

A total of 312 completed surveys were usable for the choice analysis resulting in 4680 choice observations; this excludes the returned surveys that were insufficiently completed. A major reason for the relatively low response rate could be that the survey was conducted in the year following earthquakes in Canterbury, which caused stress in the

3.1. Statistical Choice Data Analysis

Table 2 Sample characteristics.

Incomeb

Ageb

Educationc

Employmentb

Ethnicityb Genderb

$0–$20,000 $20,001–$40,000 $40,001–$100,000 N$100,000 20–29 30–49 50–69 70b High School Trade Undergraduate Postgraduate Unemployed Employed/self–employed Not in labour force Māori Female

Non-Māori sample (%)

Māori sample (%)

Total sample (%)

Canterbury population (%)

6 12 55 27 10 29 42 17 25 26 34 13 1 70 28 – 46

3 30 36 30 14 42 39 6 25 31 33 8 6 72 22 100 50

6 14 53 27 10 30 41 16 25 26 34 13 2 70 28 11 46

10 20 43 26 17 35 33 14 45 10 10 4 3 66 32 7 51

p-Valuea Total vs. Canterbury 0.12

0.11

b0.01

0.69

0.13 0.32

a P-values for Pearson's Chi-squared test of the null hypothesis that the frequency distribution of the observed (total) sample demographic variable is consistent with the population distribution provided by Statistics NZ Census data. A p-value less than 0.01 indicates a statistically significant difference between the distributions at the 1% level. b Statistics New Zealand 2013 Census. c Statistics New Zealand 2012 Household Labour Force Survey.

S. Miller et al. / Ecological Economics 118 (2015) 207–214

workhorse model is the multinomial logit which, while simple, is relatively strict in these assumptions hence contemporary practice favours more general options where maximum likelihood estimation is approximated through simulations (Hensher and Greene, 2003; Louviere et al., 2000; Train, 2003). For this data, the random parameter logit (RPL) model with error component (EC) specification was used as justified by model fit statistics. This type of model specification, with relaxed assumptions of the error structure, takes into account preference heterogeneity amongst respondents, panel data effects, and correlation patterns across choices and alternatives (Marsh et al., 2011; Revelt and Train, 1998; Train, 2003) where the EC can be specified to capture correlation between the two non-SQ alternatives (Scarpa et al., 2005; Yao et al., 2014). The choice probabilities were approximated using NLogitTM5.0 software with 700 Halton simulations. The specific assumptions used throughout the analysis included a standard linear additive form for the deterministic part of utility with an alternative specific constant (ASC) for the status quo (ASC = 1 if SQ, 0 otherwise). All parameters followed an unrestricted triangular distribution apart from the cost attribute which was assumed to follow a constrained triangular distribution (Yao et al., 2014). In this, the cost parameter was specified so that the standard deviation equals the mean (Hensher and Greene, 2003) to ensure meaningful WTP values. While the randomness in the denominator (cost parameter) can complicate WTP estimation, it is behaviourally more plausible than fixed cost across the population while it may also improve the model fit (Bliemer and Rose, 2013; Daziano and Achtnicht, 2014). For more detailed investigation of preferences for the qualitative attributes, effects coding was used to allow non-linearity. Reference levels were poor for QMCI and MK, and 0% for SWQ; although differing form the SQ levels (in choice sets), these specifications were used to focus on valuing improvements in attribute levels. Other variables (JOBS and COST) were treated as continuous. Interaction terms were estimated, first, to provide understanding of sources of preference heterogeneity (Birol et al., 2006; Louviere et al., 2000) towards the ASC and the cultural attribute (MK); and secondly, to test the attribute interactions covered in the experimental design. Importantly, as the split-sample analysis between cultural populations was unsuitable due to sample size limitations, the ethnicity identity effect on preferences was explored via ethnicity (Māori) covariates. Finally, as indicated, people may not pay attention to all attributes (Kragt, 2013) which may have major implications in cultural valuation (Carlsson et al., 2010; Zander and Straton, 2010). This was tested in a separate analysis utilising selfstated serial attribute non-attendance questions (Carlsson et al., 2010) and restricting the ignored attributes with zero weights in the dataanalysis (Kaye-Blake et al., 2009). This model, however, had no qualitative improvement in the model fit and is thus not considered further here. 3.2. Random Parameter Logit–Error Component Model Results The majority of attribute coefficients were statistically significant at the 99% confidence level with a priori signs (Table 3). Overall, respondents preferred alternatives with more jobs, and higher levels of improvements in water quality for habitat, swimming water quality and mahinga kai. In contrast, they were less likely to select alternatives with higher cost and fair habitat quality. Regarding the cultural attribute, only two of the levels, change from poor to below and poor to above average MK, were significant and positive determinants of choices implying indifferent preferences towards the other levels. Moreover, preference heterogeneity was evident for all attributes as indicated by mostly significant spreads for the random parameters. In particular, this supports use of random parameter specification for the cost attribute (Zander et al., 2013). The positive interactions suggest, firstly, that Māori and females were more likely to select alternatives with the higher MK outcomes, thus indicating more positive preferences towards improving cultural based wellbeing. Secondly, the

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Table 3 Estimates for the random parameter logit–error component model.

ASC (SQ) JOBS QMCI fair QMCI good QMCI excellent SWQ 20% SWQ 40% SWQ 60% SWQ 80% MK below average MK average MK above average MK exceptional COST ASC (SQ)*Income ASC (SQ)*Māori MK*SWQ MK*Female MK*Māori Error component sigma: management options A vs B Model fit statistics Log likelihood Pseudo R2 AIC Number of observations

Coefficient estimates

Spread of random parameters

Coefficient

Coefficient (Std err)

−0.657 0.003*** −0.223*** 0.552*** 2.289*** 0.430* 0.555*** 0.663*** −0.255 0.500* −0.124 0.531*** −0.707 −0.019*** −0.140* −2.177*** 0.087* 0.202*** 0.208* 2.696***

(Std err) 0.445 0.000 0.079 0.142 0.212 0.222 0.129 0.134 0.353 0.267 0.178 0.175 0.495 0.001 0.080 0.779 0.048 0.072 0.126 0.186

0.009*** 0.850*** 0.754* 2.599*** 0.886*** 0.340 1.032*** 2.719*** 1.830*** 1.163* 1.077** 0.531 0.019***

0.001 0.261 0.437 0.263 0.335 0.570 0.335 0.297 0.296 0.632 0.436 0.814 0.001

−2955.718 0.4251 5975.4 4680

***, **, and * denotes statistical significance at the 1%, 5% and 10% levels, respectively.

interaction between the SWQ and MK attributes indicates that these attributes together have a positive impact on choices where respondents were more likely to select alternatives with higher level in one attribute subject to the outcomes of the other attribute (Hensher et al., 2005). Overall, these results imply public support for freshwater improvement work wherein cultural elements share a significant role, potentially to be considered collectively with swimming water management. For both of these attributes the moderate, rather than the highest policy target, may be adequate in this five year timeframe indicated by the significant preferences only up to 60% (SWQ) and above average (MK) levels of improvement. The coefficient for ASC was not statistically significant, however, the interactions suggested that Māori respondents and those with a higher income were more likely to select the non-SQ alternative (negative ASC interaction). This is consistent with Tait et al. (2012) who found a similar effect amongst females and people with higher household income. A significant EC between the two non-SQ options indicates existence of status quo bias occurring in the stochastic part of the model (Scarpa et al., 2005; Yao et al., 2014). Possible reasons for the SQ-behaviour include loss aversion (Kahneman et al., 1991) as suggested by Marsh et al. (2011) and Marsh and Phillips (2012) in similar contexts in New Zealand, or that the SQ levels either provide satisfaction for the respondent or that the perceived difficulty of trade-offs in policy outcomes leads to selection of SQ (Domínguez-Torreiro and Soliño, 2011). In the present study, avoiding increased cost appeared as the dominant reason amongst those 25 respondents who chose only the SQ alternative. 3.3. Willingness-to-Pay Estimates Based on the above model specification, the unconditional marginal WTP values for the statistically significant attributes were simulated and these are summarised in Table 4. As the cultural attribute was

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Table 4 The willingness-to-pay (NZ$) estimates(a). Element of wellbeing Employment Environment(b)

Social/ Recreation(c)

Cultural(b)

1 new jobs 173 new jobs(d) QMCI: fair QMCI: good QMCI: excellent SWQ: 20% SWQ: 40% SWQ: 60% MK: below average for Māori MK: above average for Māori

Median

5th percentile

95th percentile

0.16 27.68 −11.78 30.21 122.55 23.69 29.53 35.88 28.53 38.96 28.10 40.69

−0.08 −13.84 −25.43 1.61 22.82 −6.12 9.96 0.28 −24.14 −18.25 −4.44 1.39

1.32 228.36 48.31 152.89 597.35 155.46 110.49 197.42 259.89 294.68 179.80 215.45

a) Annual for 5 year timeframe; reference levels: b) poor and c) 0%; d) WTP estimates are multiplied by 173.

found to have significant interactions with the Māori respondents, this was taken into account in the WTP estimation (Hoyos et al., 2009) as follows:  ^ WTPMK for Māori ¼ − β MK  ^ = β

 ^ ^ þb std:dev: þ β MKMāori  ^ ^ þb std:dev: þ β

above average

MK above average

COSTMāori

where the coefficient estimate for COST*Māori was not statistically significant (thus not included in the final model) and hence equals to zero. Considering the estimated median values, people were willing-topay most for the change from poor to excellent environmental quality ($123/year) and this was at least three times higher than other WTP estimates ($24 to $41/year). In contrast, WTP for fair environmental quality was negative suggesting perceived disutility given the option to choose alternatives with other levels. Within these estimates, mahinga kai sits in the mid-range of values where both levels of improvements have approximately the same WTP. This implies possible insensitivity to scope towards MK, potentially to be explained by diminishing marginal utility amongst other proposed reasons such as respondents' perceptions of the success rate of large scale improvements (Lew and Wallmo, 2011). More importantly, a significant finding was that Māori have approximately 40 percent higher WTP ($40/year) compared to the general population ($28/year). Overall, the results demonstrate the balance of the different freshwater policy targets and signposts significant public WTP for improving cultural outcomes. WTP for improvement in environmental quality, swimming water quality and increase in employment were generally similar to previous New Zealand studies (Kerr and Swaffield, 2007; Marsh and Phillips, 2012; Marsh, 2012; Tait et al., 2012). Overall, the results show a positive WTP for all attributes. People were willing to pay most for the change from poor to excellent environmental quality; and the WTP for creating 173 jobs, while valued positively, was slightly lower in relation to other outcomes. It has been suggested that jobs created in the rural areas, where irrigation is likely to happen, can be considered as public good (Marsh, 2012) providing economic and social benefits for the wider population (Birol and Cox, 2007; Colombo et al., 2005). The use of different units (e.g. verbal and numeric) for attributes, however, presents difficulty in the comparison of marginal WTP between attributes and their objectives in the given timeframe (Carlsson et al., 2010). The value for improvement in cultural outcomes is similar to findings in the international literature where cultural values have often been found positive, although not the highest relative to other attributes considered (Birol et al., 2006; Carlsson et al., 2010; Rolfe and Windle, 2003). Furthermore, indigenous cultural populations have been found to have higher WTP towards their cultural values (Rolfe and Windle, 2003; Zander and Straton, 2010), however, the general population can

also hold significant values for cultural outcomes, such as existence or bequest values (Birol et al., 2006; Oleson et al., 2015; Zander et al., 2013). This was also supported in the present study as the cultural attribute over the whole sample, including both cultural populations, had a positive WTP for improvements. 4. Conclusions Freshwater resources provide wellbeing to society in many diverse ways. Broadly these can be categorised as environmental, economic, social and cultural wellbeing. Of these, this paper focused on assessing how Canterbury residents value the protection and improvement of the cultural dimension in the region's rivers, reflecting the values of indigenous Māori culture attribute, in relation to other economic and environmental values. It is important to ensure these cultural values are respected and understood when considering freshwater related development in the region (Tipa, 2014). This study builds on the CE literature of freshwater valuation by providing evidence from a New Zealand based case study with a culturally specific attribute. In this study, indigenous cultural values were measured through a mahinga kai attribute based on Tipa and Teirney (2003) work; this attribute was constructed in order to explicitly separate cultural values from the other water quality attributes of recreation (focusing on swimming rather than fishing) and environmental quality. The study provides information for freshwater management of public support for indigenous cultural values consistent with the holistic policy framework, and for environmental non-market valuation practitioners about the importance of relevant cultural values. An important implication concerns the omission of cultural uses from valuation leading to potentially substantial impacts on welfare estimates and subsequent decision making. The study shows that improvement in mahinga kai was significant and valued in the mid-range in relation to environmental, recreational and employment attributes, approximately $28/year, hence indicating significant support for the protection of Māori cultural values alongside other values. However, there are challenges in measuring traditional cultural outcomes in economic valuations. Another interesting result was that Māori have higher WTP towards the cultural attribute, approximately $40/year, although this result is indicative only due to a relatively small amount of Māori respondents. The key message that these results demonstrate is that cultural values are considered important to the wider New Zealand public, and not just for Māori. The results of this study could be used to guide prioritisation in budgeting for quality improvement work in rivers and streams where policy should include improvement on mahinga kai sites, as this is preferred by all residents. In addition, a significant attribute interaction was found between the cultural and recreational outcomes which may suggests that these elements might need to be considered, at some degree, collectively in the water management. These lessons of public preferences are useful for the planning of natural resource management in holistic strategy frameworks, in particular when resources are considered culturally important. This study contributes to the limited international literature of indigenous cultural valuation in a freshwater context. The results were similar to the previous studies, hence demonstrating how WTP in the context of culturally important resources could be potentially undervalued if these significant cultural elements are omitted. One reason for the lack of research has been critique involved with monetisation of cultural values, however, neglecting them from valuation would risk not communicating the positive utility provided. The findings from this paper support the view of Awatere (2005) that cultural values should not be disregarded in economic valuation but that the difficulty of measuring these in money metric should be confronted rather than ignored. This measurement issue is not new (Satterfield et al., 2013) but requires attention. In this study, this was addressed by trying to find an attribute that is based on cultural

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knowledge and that would be measurable, salient and aligned with policy objectives. This work would benefit from split-sampling studies between relevant cohorts. In order to take these findings further, environmental CE studies could consider the inclusion of the cultural values, where relevant, in order to mitigate possible biases. The future research could consider other ways to measure and present the traditional culture attribute, such as comparing verbal and numeric versions, or to include other attributes that may impact on valuation. Related to this, the future research could explore preference heterogeneity regarding where the outcomes would occur or who would benefit, such as improvement in local rivers or local employment. Secondly, this study covered region's rivers collectively, however, it is possible that preferences may differ over resources that are known to be culturally important, such as Lake Ellesmere/Te Waihora in Canterbury. In relation to this, another research direction could explore preferences towards practical means to provide these benefits, such as a Māori culture-specific management practices. This study provided an incremental step towards the systematic measurement of cultural values alongside other attributes in freshwater management.

Acknowledgements This research was funded by the Agribusiness and Economic Research Unit (AERU) at Lincoln University, New Zealand. The authors would like to acknowledge the contribution of Dr Simon Lambert at Lincoln University for providing advice on Māori culture; and the two anonymous reviewers for their insightful and constructive comments.

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